It is known to provide eyeglasses of the type in which lenses, each capable of changing color in response to an applied voltage, are mounted in an eyeglass frame and are connected to a power supply separately provided within the eyeglass frame (refer, for example, to patent document 1).
It is also known to provide a method for producing a liquid crystal display panel, in which a liquid crystal is injected through a tiny injection port provided in a spacer interposed between substrates and, after sealing the injection port upon completion of the injection of the liquid crystal, an adhesive material is injected into the gap created outside the spacer and is cured to complete the production (refer, for example, to patent document 2).
However, if a path in the liquid crystal display remains that was used for injecting the liquid crystal, since this path has different optical characteristics from those of the other portions, there are problems when it is used, for example, as an eyeglass lens, the lens wearer may be uncomfortable when using them. There has also been the problem that, when cutting the lens to fit the shape of the eyeglass frame, since the liquid crystal injection path, if left in the panel, cannot be cut, the outer shape of the lens cannot be obtained as desired to fit the shape of the eyeglass frame.
It is also known to provide a method for producing a large-area liquid crystal display panel wherein in order to maintain the gap between two substrates, two sealing agents are placed one inside the other and, after dropping a liquid crystal material into the space inside the inner sealing agents, the substrates are bonded together to form a liquid crystal panel, after which the outer sealing agents is removed to complete the production (refer, for example, to patent document 3).
The liquid crystal dropping method eliminates the need for forming a liquid crystal injection path in the liquid crystal display panel but, when using the panel as an eyeglass lens or the like, the outer shape of the liquid crystal panel needs to be edged to fit the eyeglass frame of any given shape. Therefore, it is difficult to predetermine the positions of the two sealing agents.
There is also disclosed a light-adjusting display structure comprising a pair of transparent substrates, wherein a slot is formed in one of the two transparent substrates, and a feed member is inserted in the slot from one end of the light-adjusting display structure to feed the light-adjusting display structure (refer, for example, to patent document 4).
Patent document 1: Japanese Utility Patent Publication No. H03-35523 (FIGS. 1 and 3)
Patent document 2: Japanese Unexamined Patent Publication No. S52-28296 (FIGS. 1 and 2)
Patent document 3: Japanese Unexamined Patent Publication No. 2000-305060 (FIGS. 6 and 9)
Patent document 4: Japanese Utility Patent Publication No. H04-91338 (FIG. 1)